My real reason for asking was not whether the SCR would work to vary the
voltage, that's done all the time, but it does put spikes in the AC
waveform. I'm sure Henry never anticipated such and how the choke and
filter cap in the power supply would love that (or not).
Thanks,
73 de Jim W2XO
On 08/12/2016 03:41 PM, Michael Clarson wrote:
Jim: Motorola did something like you describe in their "MOTRAC" series
base stations (beige cabinets) in the 1960s and 70s. These were
250-350 watt output stations using a pair of 8560s as finals. They
regulated B+ with SCRs in the transformer primary. All done at 60 Hz
and never had any RFI issues from these supplies. I do not have any
manuals. Later versions of these stations used constant voltage
transformers. Good luck finding a solution. --73, Mike, wv2zow
On Fri, Aug 12, 2016 at 1:07 PM, Jim Durham <jimdur@gmail.com
<mailto:jimdur@gmail.com>> wrote:
Hello all,
This is my first posting, so Howdy..
I have a Henry 2k-2 (modified to take 3-500Zs). After I bought
it, some years back, I fired it up and tube filaments were very
bright and HV was high.
Talked to Henry. They asked me the plate transformer number, which
they looked up and said "Oh, that's the 200v European
transformer". So, I put a hefty variac on the 240v AC incoming and
all is fine, except I'd like to ditch the variac and was wondering
about if anyone on here had any wise words about using an SCR
instead to back the AC voltage off.
My experience with big SCRs (TV studio lighting) was that they
tend to put out a lot of RF hash. I also wonder about how the
choke and filter cap in the power supply would like non-sinusoidal
AC waveform?
Anyone have any experience with this?
Thanks and 73,
Jim, W2XO
_______________________________________________
Amps mailing list
Amps@contesting.com <mailto:Amps@contesting.com>
http://lists.contesting.com/mailman/listinfo/amps
<http://lists.contesting.com/mailman/listinfo/amps>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|